I love my Catrike and I love Mavic rims sooooooooooo, now they're together. I've been using Mavics for a lotto' years and they're on all my bikes. It's easy to find a nice Mavic rim in 26" and 700c sizes but not so much in the 20" size. Luckily, there is one on the front of my Tour Easy and I just bought a stockpile of them so the XY's are flowing like water around here.
I measured the ERD of the stock Catrike rims and the Mavic XY rims to see if they could be swapped out without buying new spokes.....As luck would have it, they match up very well.
The XY rim and the stock rim. The XY rim is twice the width of the stock rims and this spreads the tire out better and makes for an improved ride. Made in France with supa' high quality.....Oui.
This is an easy way to do a straight rim swap. Bread ties keep the spokes in place. Another way is to tape the rims together and move the spokes over as you take them out of the old rim.
Here's what the bread ties do. I use beeswax on the spoke threads when lacing them back up.